Her dream of competing in the Olympics became a 'reality'. [=she competed in the Olympics, as she had dreamed of doing]
He was starting to think he was infallible, so the criticism from his boss served as a 'reality check'.
Her friends gave her a 'reality check' about her boyfriend. [=told her the truth about her boyfriend]
(..) He envisioned a steamer so grand in scale... ..that its supremacy would never be challenged. And here she is... ..willed into solid reality. Hear, hear. Salmon. You know l don't like that, Rose. She knows. We'll both have the lamb, rare, (..)1997 Titanic